MAZATLAN UNIVALVES 459 



Fasciolaria aui'antiaca, Sow. Gen. no. 30 : non Lam. loc. cit. 



p. 434, no. 4. 



Mr. Sowerby, having discarded his own original name, 

 adopted another which had been preoccupied by Lamarck. 

 The dealer unfortunately cleaned the whole stock of this mag- 

 nificent species, disregarding both epidermis and opercula. 

 Shell of a rich orange, under a rather thick reddish brown 

 epidermis, striated in lines of growth ; with numerous rounded 

 spiral ridges, having broad interstices, most develoj)ed near 

 the centre of the whirls. In the middle is generally seen a 

 row of stout tubercles, sometimes almost wholly evanescent. 

 Labrum inside with finely raised reddish spiral striae. Columel- 

 lar plaits two, not conspicuous. Operculum pyi'iform, apex 

 terminal : outside with about 5 longitudinal furrows on the 

 middle and interior ; exterior with irregular diagonal ribs ; 

 inside with very large attachment, not corrugated.* Long. 11'5, 

 long. spir. 5 '7, lat. 5*4, div. 40". 



Sab. — Peru, Cuming. — Mazatlan ; not uncommon ; LJiwol Col. 



Tablet 2088 contains a solitary specimen with epidermis that 

 escaped the acid bowl. — 2089, a stronglj^ tuberculated speci- 

 men. — 2090, the largest, scarcely tuberculated specimen ; and 

 an operculum. 



Sttb-Family MITRINiE. 



These creatures, so numerous in form and varied in i)ainting 

 in the E. Indian Islands, are said not to be partial to a con- 

 tinental life. Very few species are found on the W. coast of 

 America, and only two, of very sombre aspect, occur in the 

 Mazatlan collection. 



Genus MITRA, Lam. 



Mitra, Lam. Journ. Sist. Nat. 1799, (pars.)— ^. Sj A. Ad. 



Gen. vol. i. p. 168. 

 Thiarella, Swains. 



585. MiTEA LENS, Mawe. 



Voluta lens, Wood Lnd. Test. Suppl. 1828, pi. 3, f. 25. (f. 28, 

 sec. Mke.) 



* A few of these opercula having dropped into the PTTiilii box, while all the 

 shells were taken away to the acid, I unfortunately distributed them as the 

 opercula of the latter. Authentic specimens of each species in Capt. Kellatf 3 

 collections, verified the correction of the mistake. 



